1. Field of the Invention
This invention relates generally to video tape recorders and other apparatus in which a tape is wound about a guide drum for action on the tape, for example, for having signals recorded on, or reproduced from the tape, and the invention is more particularly directed to an improved tape guiding device for such apparatus.
2. Description of the Prior Art
In the standards established by the Society of Motion Picture and Television Engineers (SMPTE) for one-inch type-C, helical-scan video tape recording, it is specified that the tape entrance and exit guide elements for guiding the tape wound about the guide drum in an .OMEGA.-shaped configuration should provide a tape wrap angle such that the video record vertical-interval dropout is 10.00.+-.0.25 horizontal lines due to loss of head-to-tape contact, with no electronic switching of the recording signal. It is inherent in such standard that the tape entrance and exit guide elements be operatively positioned relatively close to each other and also close to the peripheral surface of the drum. Although it has been the practice, for example, in the broadcast quality video tape recorder available under the designation BVH-1000A from Sony Corporation, the assignee of the present application, to mount the tape entrance and exit guide elements for relatively small movements in various directions relative to the tape guide drum, such small movements are only for the purpose of effecting tracking adjustments and do not substantially affect the distances between the entrance and exit guide elements or between the latter and the periphery of the guide drum. Thus, the tape entrance and exit guide elements, in existing VTRs provided with the type-C helical-scan video tape recording format, remain relatively close to each other and to the peripheral surface of the guide drum when the tape is being wound about the guide drum, or unwound therefrom. Therefore, it is quite difficult to wind or wrap the tape on the guide drum and to remove the tape therefrom, and there is the danger that the tape may be damaged during such operations, particularly when seeking to engage the tape in the narrow clearances between the tape entrance and exit guide elements and between the latter and the peripheral surface of the drum.